Emma Stone, Superbad

Stone's big break came thanks to Judd Apatow, who cast her in 2007's Superbad. Apatow was also, interestingly enough, responsible for the red hue that would become her signature. "I had been blonde my whole life," Stone told BellaSugar in November 2011. "[At casting] Judd Apatow walked in and said, 'Make it red.'"